People who as children I imagine where the kind who poked you over and over and over as you ignored them and moved away. They found you and poked you again. It didn't hurt, it was just annoying. These same children grew up to be adults who poked with sarcasm but now, when you ignore them, they not only find you to poke you some more, they think they are wittier and savvier than you because you don't fight back in kind. "Hey, look at that, I not only insulted her, she probably didn't even get it." I'm here to tell you "I got it. Now back off before you get hurt." Because if it's a sarcasm battle you're looking for, get ready.
If your family was getting in the car and it was around dinner time and a neighbor passing by slowed down to say hello but added "Where are you off to? McDonalds?" with a smirk, you'd be offended, right? But instead of saying something equally obnoxious you say "um, no" and get in the car. She moves on thinking, "poor, fat slobs, they thought I was being serious" and you're left wishing you had a thrown a rock at her windshield along with a good comeback.
Now, if I were so inclined to pursue my own mudslinging, I might say something like "Yes. Would you like us to pick up something for you and the kids? I hear your husband is out of town on "business" again. He sure is away a lot..." Granted, my comeback had a bit more bite (and my husband might say, far too subtle) than some fat joke but let me ask you this... after that kid poked you repeatedly every recess for weeks, didn't you want to break his finger?
The high road is unsatisfying. OK is sucks! But the low road puts you on the same level with the jerks. What's the answer? I remind myself about a little thing called karma. What goes around comes around. It may not happen immediately, but it will happen. Oh, and when it does, I'll be hoping I'm there to bear witness to the carnage - uh-oh, my low road is showing ;-)